This invention relates in general to methods of manufacturing water resistant electrical connections. In particular, this invention relates to an improved method of heat shrinking a protective sleeve onto an electrical connection to provide a water resistant covering therefor.
In many automotive and other applications, electrical wires are used to connect electrical devices with one another. Often, the ends of such electrical wires are connected to electrical termination devices, such as eyelets, terminals, and the like, that facilitate the connection of the electrical wire to the electrical device. An electrical connection may be made between an electrical wire and an electrical termination device in a variety of ways, such as by soldering or crimping, for example. In some instances, a conductor portion of the electrical wire may be formed from a first material (such as aluminum), and the electrical termination device may be formed from a second material (such as copper) that is different from the first material. When the electrical wire and the electrical termination device are formed from different materials, a water resistant covering may be provided over the electrical connection because water can cause corrosion to occur at the junction of the different materials used to form the electrical connection.
It is known to provide such a water resistant covering in the form of a hollow protective sleeve that, when subjected to heat, shrinks onto the electrical connection between the electrical wire and the electrical termination device. Typically, the protective sleeve is a plastic tube having an inner surface that is coated with an adhesive. The protective sleeve is initially positioned about the electrical connection, then is subjected to heat. Such heat causes the protective sleeve to shrink until the adhesive on the inner surface of the sleeve engages the electrical connection. The heat also causes the adhesive to seal the protective sleeve to the electrical connection. Thus, the protective sleeve provides a water resistant covering for the electrical connection.
In the past, an external radiant heat source has been disposed about the protective sleeve in order to generate the heat necessary to shrink the protective sleeve onto the electrical connection as described above. Although the use of an external radiant heat source has been effective, it is known that the heat from such an external radiant heat source must pass through the protective sleeve in order to reach the adhesive provided on the inner surface thereof. This is undesirable for several reasons. Thus, it would be desirable to provide an improved method of heat shrinking a protective sleeve onto an electrical connection that avoids this issue.